Text Size

During the Copenhagen talks, richer countries set a goal to “mobilize” $100 billion a year in financial aid by 2020. Poorer countries want more details on how that money will be doled out.

“Without a commitment on finance, you will not get developing country engagement,” de Boer said.

But Stern said in London that “no step change in overall levels of public funding from developed countries is likely to come anytime soon.”

“The fiscal reality of the United States and other developed countries is not going to allow it,” he said, citing “huge” domestic obligations for needs like education, health care and an aging population.

Still, Stern said it’s possible to use public policy to attract private capital for financial assistance. “The well of private capital is deep, but we need hard work by developed and developing governments to tap into it,” he said.

De Boer offered one possibility for leveraging private capital — though it would most likely meet intense resistance in the U.S. “I think the most effective way to do that is pricing carbon and allowing market mechanisms to work,” he said.

4. The Poland factor

Many of the activists flocking to Warsaw would like to see nations phase out their use of coal. But Poland is embracing the fuel, relying on coal for the vast majority of its electricity and resisting European proposals to push greener alternatives.

In one bit of symbolism, the coal industry is hosting an international conference in Warsaw during part of the climate talks.

Some groups have expressed frustration about the location of the talks.

“The dirty energy lens on it is certainly not helpful,” said Heather Coleman, policy manager for climate change at Oxfam America, though she added that Poland’s stance probably won’t set back the negotiations.

But others note that Poland isn’t the only country that relies on coal — and any successful climate negotiations will have to involve those nations.

“There are many places in the world that are heavily dependent on coal, and we have to find an agreement that they can participate in,” Petsonk said. She added, “Some people say Poland is more like Ohio.”

5. Specter of climate warnings

Meanwhile, scientists say the Earth’s clock is ticking.

The World Meteorological Organization warned Wednesday that the amount of greenhouse gases in the atmosphere spiked to a record high last year. And a U.N. report Tuesday raised doubts that any climate agreement can limit the rise in global temperatures to an amount that scientists consider low enough to avoid serious harm — 2 degrees Celsius compared with pre-industrial levels.

The latest warnings follow a stream of other research that has sounded alarms about rising sea levels, harsh droughts and other extreme weather if policymakers don’t act soon.

“We clearly are not on track both in speed and scale,” said Jennifer Morgan, director of the climate and energy program at the World Resources Institute. “There’s a large gap that needs to be closed, and the longer you wait to close the gap, the more expensive it becomes.”

De Boer acknowledged that even “under the most optimistic scenario, 2015 is not going to provide the final definitive answer to the climate challenge.”

“I don’t think that Paris in one fell swoop can give us the definitive answer on how to limit temperature increases to 2 degrees centigrade,” he said. “But it can, and it must take a very serious step forward in that context.”